Improvement in self-locking screw-bolts for safes



CHARLES O. YALE.

lmprovemeryt in Self-Locking Screw-Bolts for Safes. vNo. H5,007.-Patented Mag 16,1871.

fitted cam.

CHARLES 0. YALE, or NEW/YORK, 'N. Y.

Letters Patent No. 115,007, dated May 16, 1871.

IMPROVEMENT IN SELF-hOCKlNG SCREW-BOLTS FOR SAFES.

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom. it may concern Be it known that I, CHARLES O. YALE, of thecity,

county, and State of New York, have invented an Improved Self-lockingScrew-Bolt for Safes, of which the following is a specification.

This invention relates to the securing of conical screw-bolts used inthe construction of safes for bold ing together'the several layers ofmetal of which the -wall of the safe is constituted-.

Heretofore screw-bolts have been fastened by running a out onto thesmall and protruding end of the bolt on the inside of the safe.

My invention has for its object the securing of the bolt in such amanner that when screwed home it shall be self-locked in place, and nopart thereofbe leitprojecting from either side of the wall, making abolt. which never can be removed when finally put in its place.

To enable others skilled in the art to make and use my invention, I willproceed to' describe the same.

In the drawing annexed- .A is the screw-bolt.

-It passes through several thicknesses of iron, 0 e f 'i g, 0 being theinner and g the outer surface.

Hrepresents a nut secured in a metal plate, 0.

In one side of the nut a recess, j, is formed, and ,in this is inserteda pawl, k, fitted to slide freely therein.

In the threaded portion of the bolt a notch or groove is formed, and-theshape of the groove and that of the end of the pawl k are such that whenthe bolt is being screwed'into'tbe hot, or vice oersa, the notch acts asa ratchet to throw the pawl out of saidnotch; but at each revolution ofthe bolt a spring, I, behind the pawl, pushes it into the notch andprevents the bolt'from being unscrewed.

'When,-therefore, the bolt is once sent home, the pawl 76 takes into thenotch and permanently looks it in place.

The bolt is turned by a wrench adapted to take hold of pins ordepressions m on the head of the bolt, such pins or depressions to beafterward filled up or removed.

In some cases it may be found desirable to have the pawl on the bolt andthe groove in the nut; and I have also indicated (in dotted lines) infig. 3 an alternative for the sliding pawl in a swinging pawl, the

operation of which is to bind on the\bolt at any point thereon, when thebolt is turned backward.

To further secure the bolt against the possibility of being unscrewed,the nut is purposely made circular and held stationary while the bolt isbeing screwed in by a fragile device, such as the pin N, set in themetal plate 0.

Such device is sufficiently stout to. prevent the turning of the nutwhile the screw-bolt is free; but when locked to the nut a sudden turnof the bolt would wrench oh the pin, when the nut H will re-' volve withthe bolt.

4 I do not confine myself tospecific forms in the above invention, butshall vary the same as circumstances may require. 7

A similar result for bending the bolt to those de scribed is theslitting of the threaded end of the bolt and the insertion of a wedge,to be driven in by screwing. the bolt into its place, the nut beingpreviously tapped tapering from the back side.

I claim as my invention and'desire to secure by Letters Patent- I Aself-locking screw-bolt for safes, as herein described, constructed,applied, and used, substantially as and for the purpose specified.

' 4 CHAS. O. YALE.

Witnesses E. H. SMITH, W n. H. JOHNSON.

